Plugs

[h2osk8er00]

I saw some threads on performance plugs.. but when looking for part numbers and all that.. I found these plugs from the NGK website.. so I Googled them and thought I'd ask if anybody has ever used them...

http://www.amazon.com/NGK-Iridium-Sp.../dp/B0033HZQUG

[h2osk8er00]

Also... what about this cap.. funky looking but does it work? anybody use it?

http://www.ebasicpower.com/pc/MAL9-29419/MER10D

[Wickedcummins]

I can tell you there is no better plug for your engine then it came with. Your timing cure/duration and coil firing freq and everything else. Run OEM it will be your best chance to get the best power output!

[Joeprunc]

I've never used NGK plugs on an American motor.

[skippabcool]

I can tell you there is no better plug for your engine then it came with. Your timing cure/duration and coil firing freq and everything else. Run OEM it will be your best chance to get the best power output!

Good to know Wicked. Now I won't be tempted to spend the extra for something that I don't need. My buddy had said that he has tried every kind out there, for better performance or gas mileage / hours and he thought that it did run better with what it called for.

I have spent extra for the plugs on my lawn tractor and lawn mower and it does seem that the ones it comes with are the best.

[h2osk8er00]

So these are the standard ones? Or do I need to go through Mercruiser?

http://www.autozone.com/autozone/par..._&viewAll=true

[Wickedcummins]

Your engine cover or owners manual should have the plug number it came with.

[h2osk8er00]

Your engine cover or owners manual should have the plug number it came with.

Word.. Thanks Wicked.. Never thought I'd say that... JK

[TeamAllen]

I've never used NGK plugs on an American motor.

I'm the exact opposite. I use NGK in every motor. BPR6EFS (3623) in my Mercruiser.

[h2osk8er00]

So I went to replace the plugs and found plug number 4 (from the firing order) to be very black compared to all of the rest.. not to mention 3 plugs cracked upon carefully removing them.. what could be the casue of this? The plugs all had the paint on them and I did buy my boat from a dealer 3 years ago.. but I am thinking these plugs were at least 4-6 years old.. Any thoughts on what effect this could have on my engine? also I tried to get the cap from an Automotive store but bought the wrong one of course.. what vehicle do modt of you go off of for an MIE 350 MAG MPI SKI engine.. SN is L672833 I believe... Had trouble making the numbers out on a picture I took and the boat is at home..(I'm at work).. The cap I bought was from an old cadilac and it was wrong.. I need the distributor cap with 4 screws and this one only had two. Should I just go to a marine shop and get an OEM Cap or will the ACDelco one suffice?

[h2osk8er00]

Oh Yeah.. when I put the new plugs in and a new IAC valve.. boat started up and purred like a damn kitten... of course we were on dryland but I could definitely tell something was different.. Seemed to start after the first turn of the key too instead of being slightly delayed as usual.. hope to get her out tonight after work! Maybe I'll tkae her out without the new cap to see if that was an issue as well..

[Wickedcummins]

I personally change the plugs every year! You should run some BG 44k with a tank full of gas

[h2osk8er00]

I personally change the plugs every year! You should run some BG 44k with a tank full of gas

Do you notice a performance difference in doing the spark plugs.. I'm thinking those plugs wer 6-7 years old.. I'm hoping my gas mileage to increase a little to.. been eating that stuff like it comes outta the ground for free.. oh wait.. it sorta does..